Electrohydraulic motor vehicle control devices, such as pressure control apparatuses (hydraulic and electronic control unit, HECU) for brake systems, commonly exhibit an arrangement which comprises an electronic control unit on one side, a hydraulic unit in the middle, and an electric motor unit for a hydraulic pump on the opposite side of the pressure control apparatus. The control unit makes contact with the electric motor unit with the aid of a pump motor adapter which is known per se. Electromechanical control units, such as transmission control units for example, and also electrohydraulic control units often have a conductive, in particular metallic, housing part and an integral or multipartite housing part which is composed of plastic. The two housing parts often also jointly form the outer boundary of the control devices at the same time.
During operation, electrical potential differences between the main body of the hydraulic unit, which main body is composed of an electrically conductive solid material, and/or the electrically conductive housing part and the electronic control unit can lead to faults, damage or destruction of sensitive electronic components and therefore have an adverse effect on the availability of the respective system which is to be controlled, and on the safety of personnel. Therefore, stringent requirements are placed particularly on electromagnetic compatibility and in respect of protection against electrostatic discharging. Establishing an electrical connection between different conductive components in order to establish potential compensation is known per se.
The focus for electrical contact-making means in motor vehicle control devices is, in addition to a robust design, also a small structural and functional central insert. In this case, robustness is to be understood as meaning, for example, vibration resistance, corrosion resistance, temperature resistance and resistance to aging.
Sealing-off at the inlet point into the housing is problematical for an insulated ground strap which is routed from the vehicle body, as reference potential, by means of a sealed contact plug, into the housing of the electronic control unit since water can enter the housing through the sealed-off contact plug owing to the capillary effect of the insulated braided ground strap and can destroy the contact plug and also other components.
Prior application DE 102 012 219 579, describes a connection of a reference potential of a vehicle by means of a hydraulic unit, wherein a connecting contact is provided between the hydraulic unit and a printed circuit board, this creating a main current connection of the reference potential of an electronic control unit.
Prior application EP 12 464 013, describes an electrohydraulic pressure control apparatus for motor vehicle brake systems, which electrohydraulic pressure control apparatus has an electrically conductive connecting contact between a hydraulic unit and an electronic control unit, which electrically conductive connecting contact comprises an elastic or spring-action means along the longitudinal axis. There is enormous cost pressure on all of the components on account of the high numbers in which motor vehicle control devices are produced. In this case, factors which drive price include, in particular, saving on material and also on process steps during production. It is also necessary to further reduce the space requirement and the weight of existing systems and nevertheless to at least maintain or to improve availability in the process.
The object of the invention is to provide an electrohydraulic or an electromechanical motor vehicle control device which better meet/meets the requirements of modern and future control devices.
This object is achieved by an electrohydraulic and/or electromechanical motor vehicle control device as described herein.